Malicious backdoors and intentional security flaws in hardware designs pose a threat to trusted computing. A designer can hide a backdoor within a hardware design by including a circuit design (e.g., through inclusion of a few lines of malicious code, out of potentially millions, representing circuit designs) in a way that slightly deviates from specification. For instance, a hardware backdoor, when triggered, might turn off the page protections for a certain range of addresses. Such backdoors can be inserted either by third-party designers producing independent components or by rogue insiders.